The Internet Archive and the University of Maryland launch such a library, and it's free to anyone with an Internet connection. Kids helped design the library, and they had final say on the books. NPR's David Kestenbaum reports.

Each summer, as college students prepare to leave campus, they get rid of their textbooks, selling them for cheap. And Bob Peterson and Kenny Jacobson are waiting to buy them, and resell them when school is back in session and demand is high. Their scheme sounds simple, and it is. They've noticed a difference in price, and they're turning it into a quick profit.

Note: This episode originally ran in 2015.Spreadsheets used to be actual sheets of paper. Sometimes, a bunch of sheets of paper taped together.

Any calculation made on a spreadsheet was done by hand, and these could take days to complete for an accountant or bookkeeper. It was tedious. One little adjustment to these calculations meant a whole day of erasing and filling the same boxes out again.

The online furniture company Wayfair is now one of the most shorted stocks. Our Planet Money team talks to its CEO about what it's like to be running a company when some investors are betting on your fall.

On January 1, 20 states raise their minimum wage and several states have additional increases planned in the coming months. Yesterday, we learned that Walmart will raise its base pay to $9 an hour this April.